I totally agree. And the absolute worst is if you’re trying to take a photo of something on the shaded side of a tree on a bright sunny day: the reflected light off of whatever you’re wearing totally screws up the color. (I have a bright orange wind breaker that I’ve learned I can’t wear while trying to do photography on sunny days. :) The black fleece is much better. Yeah, overcast is definitely best. Both lichens and mushrooms have this convenient feature: they don’t blow around in the wind like flowers!, so you can take as long exposures as you like with a tripod. Mushrooms additionally like growing on the ground where my little hiker’s tripod works just fine.

That’s a good idea – to take a dry lichen photo first. But in reality, I only use the water bottle trick once in a while. The reason being – I don’t like going out photographing in the full sun, since the sun ruins some photos. While I can lean over the lichens on the small rocks or fallen trees and also most mushrooms to block the sun, lichens on the trees are the toughest ones. Either on the sunny or shady side of the tree, most likely the photo will come out ugly. I prefer cloudy weather, but not too gloomy so there is enough light. Usually after rain but before it clears out is ideal – and lichens and some mushrooms (like some crust fungi and jelly and some ascomycetes) are colorful and juicy. But weather doesn’t always cooperate, so I have to use water trick (and block the sun too – the colors in the sun and in the shade come out strikingly different in my camera too). Also, most of my forays are to the wet and cool places – that’s where majority of the mushrooms are, and no extra water is needed.

I’m sure the lichens love you for it, but you’re also sure making our life difficult! As you well know, lichens can look radically different wet and dry. I typically only deal with dried specimens, so you throw most of my experience right out the window with that bottle of water. :) (Seriously, though, I’ve learned several things from the exercise, as well. Maybe I could suggest taking at least one dry photo first, though…)

I like photographing lichens in their wet colors, so I usually pour some water on them from the bottle I carry. That’s what produced the striking color of the rocks, as far as I remember – otherwise they’re little bit paler (just like lichens).